1. Field
One or more embodiments relate to an apparatus and method to encode and decode a multi-channel signal, and more particularly, to an apparatus and method to encode and decode a multi-channel signal using phase information.
2. Description of the Related Art
A parametric stereo technology may be used to encode stereo signals. The parametric stereo technology may down-mix an input stereo signal to generate a mono signal, and may extract a stereo parameter that indicates side information associated with the stereo signal. The parameter stereo technology may encode the generated mono signal and the extracted stereo parameter to encode the stereo signal.
Examples of the stereo parameter may include an inter-channel intensity difference parameter (IID) or a channel level difference parameter (CLD), an inter-channel coherence parameter or an inter-channel correlation parameter (ICC), an inter-channel phase difference parameter (IPD), an overall phase difference parameter (OPD), and the like. The IID or the CLD indicates an intensity difference according to an energy level of at least two channel signals included in the stereo signal. The ICC indicates a coherence or a correlation between the at least two channel signals, included in the stereo signal, according to a similarity of wave forms of the two channel signals. The IPD indicates a phase difference between the at least two channel signals included in the stereo signal. The OPD indicates how a phase difference between the at least two channel signals included in the stereo signal is distributed between two channels, based on the mono signal, and the like.